12509906 has 4 divisors (see below), whose sum is σ = 18764862. Its totient is φ = 6254952.

The previous prime is 12509869. The next prime is 12509911. The reversal of 12509906 is 60990521.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 60990521 = 311 ⋅196111.

It can be written as a sum of positive squares in only one way, i.e., 12075625 + 434281 = 3475^2 + 659^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3127475 + ... + 3127478.

Almost surely, 2^12509906 is an apocalyptic number.

12509906 is a deficient number, since it is larger than the sum of its proper divisors (6254956).

12509906 is an equidigital number, since it uses as much as digits as its factorization.

12509906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6254955.

The product of its (nonzero) digits is 4860, while the sum is 32.

The square root of 12509906 is about 3536.9345484473. The cubic root of 12509906 is about 232.1407315985.

The spelling of 12509906 in words is "twelve million, five hundred nine thousand, nine hundred six".